Q.In the electrolytic refining of copper, which one of the following is used as anode ?

In electrolytic refining, the impure metal is always made the anode (so it dissolves into solution), while a strip of pure metal serves as the cathode where the purified metal deposits — for copper, impure ('blister') copper is the anode.

In the electrolytic refining of copper, a large block of impure copper (blister copper, obtained from the smelting/converter stage, typically ~98-99% pure) is made the anode, and a thin sheet of pure copper is made the cathode, both dipped in an electrolyte of acidified copper sulphate solution. On passing current, copper from the impure anode dissolves as $Cu^{2+}$ ions ($Cu \rightarrow Cu^{2+}+2e^-$ at the anode) and migrates through solution to deposit as pure metallic copper at the cathode ($Cu^{2+}+2e^- \rightarrow Cu$). More reactive impurities (e.g. Fe, Zn) dissolve into solution but stay in solution (not deposited, since Cu is more easily reduced), while noble/less-reactive impurities (Ag, Au, …